Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DE_1968_4_2_a18, author = {V. N. Laptinskii}, title = {A certain inequality}, journal = {Differencialʹnye uravneni\^a}, pages = {368--369}, publisher = {mathdoc}, volume = {4}, number = {2}, year = {1968}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1968_4_2_a18/} }
V. N. Laptinskii. A certain inequality. Differencialʹnye uravneniâ, Tome 4 (1968) no. 2, pp. 368-369. http://geodesic.mathdoc.fr/item/DE_1968_4_2_a18/